The explicit construction of modules (irreducible and indecomposable) for the BRS and full BRS algebras are presented. The existence of parent and daughter phenomena provides a natural basis for the introduction of the metric. The structure of BRS and full BRS transformation groups and the corresponding 'Campbell-Housdorff' formulae are discussed. The relevance and genesis of BRS symmetry groups are briefly analysed in the framework of fibre bundles.